Dipper tooth



w.` G. NICHOLS May 1, 1'923.

DIPPER TOOTH Filed Dec. 30, 1918 WELEY G. NICHOLS, OF

MANGANESE STEEL MAINE.

CHICAGO HEIGHTS, ILLINOIS, ASSIGNOB TO AMERICAN" COMPANY', OF CHICAGO,ILLINOIS, A. CORPORATION OF DIPPEB TOOTH.

Application filed December 30, 1918. Serial No. 288,817.

To all whom it mag/concern:

Be it known that I, Wasuir G. NICHOLS, a citizen of the United States,residing at Chicago Heights, in the county of Cook and State ofIllinois, have invented certain new and'useful Improvements in DippervTeeth, of which the following is a speclfcation.

My invention relates to dipper teeth for dredge buckets and particularlyto a novel wa of makin the same.

n makin 'pper teeth and points therefor, it has een common practice tomake these of east metal, forming the point separately from the base ortooth ortion and providing means so that the pomts may be removablyconnected to the base portion for renewal when worn without having totake the base portion oii' the dipper. Since alloy ysteel has beeny usedin the manufacture of dipper teeth and points, heat treatment has playedan important part in the manufacture I have discovered that the sizeand's of such articles. Whenever manganese steel is used to make dipperteeth and points, heat treatment is very necessary.` In my ractice apeof the castings are important-when it comes to the matter of heattreatment. In making dipper teeth or base -portions of the usual type itis necessary that comparativelythin sections adjoin thick sections. Toprevent mis-runs, that is, to have the thin sections of correct size anddimension, it is necessary that the molten metal be at such temperaturethat the thin sections will be filled with metal. Utentimes thetemperature necessary to make the thin sections is too high for fthethick sections, the thin sections cooling more rapidly than thethick,'in which instance, the im urlties are drawn to the metal in .themollten or semi-molten state, thus causlng an excess of impurities to besegregated in' a comparatively small area which segregation is the causeof great weakne in the finished castin and failure thereof invariablyresults at t e place where the segregation is most prominent.

In heat treatment of cast sections diii-` culties are experienced inproperly treating heavy sections. Unlessthe heat penetrates the sectionsand is held long enough to dissolve the carbide along the austenticgrain boundaries-in the case of manganese steel weakness occurs whichresults in failure of the castings when put in service. Experienoe hasshown that dipper teeth designed to conformto a single standard forheavy service a're very rigid even when made of manganese steel andoften cannot absorb the shocks imparted thereto, the result bein thattheL teeth or the base castings brea y i One of the objects of myinvention is to overcome the above recited and other recognizedobjections to dipper teeth and points.

Another object is to provide dipper teeth of alloy steel so made as tobe properly heat treated and at the same time to permit manufacture oflarger and heavier teeth than can be made under the present practiceespecially as regards heat treatment.

A further object is to make dipper teeth formed of a plurality ofrelatively thin sections fastened together to make teeth of varyinthicknesses as requirements demand and w ich will be uniformlyheat-treated throughout.

A still Vfurther object is to improve dipper Ateeth for successfulcommercial use.

Generally speaking I accomplish the objects of my invention by providinglaminat-l ed base portions and points, the parts being suitably securedtogether to form unitary articles.

The above recited and other objects'will be apparent from an observationof the drawings, l wherein- Figure 1 is a top plan view partiall insection of a dipper tooth and point ma e in accordance with m invention.

Figure 2, is a side elevation of a tooth shown in Figure 1.

Figure 3 is a vertical section on line- 3-3 of Figure 2, and

Figure 4 is a section on line 4 4 of Figure 2.

The dipper tooth ofvmy invention includes a point and a base each ofwhich is formed of a pluralit of comparatively thin sections preferablyo substantially uniform thickness,l

I have chosen to show the tooth formed of three-such sections indicatedby the reference characters 5, 6, and 7. The length, shape and size ofthese several sections may be made attern or to any arrangement ofpatterns which may be useful in forming teeth of the desired shape, sizeand strength. In elevation the sections are similar to those shown inFigure 2 which is the general outline of a di er tooth base portion.vThe sections 5, 6 and) g are cast separately 'and separately subjectedto heat treat- IUE .severai sections. e .served that the only functionserved by the ment, the result being that a casting is formed` of a`uniform 'thickness so that the heat treatment is uniform throughout;that the finished section is homogeneous; and that there is nosegregation at any point therein to weaken the base. The sections areassembled in edgewise relation with the fiat surfaces in contact asshown and secured to'- gether preferably by transversely extendingrivets 8, the heads of which are preferably countersunk so as to beflush with the side faces of the base. The middle section 6 is providedwith a series of vertically extending apertures 9 through which thebolts or rivets pass to secure the base to the dipper front as is commonpractice. Referrring to Figure 3, it will be noted that the sections 5,6 and 7 are substantially of equal thickness and the rivet holes 9 passthrough the center line of the section 6 so that walls of Iuniformthickness are made at the sides of the apertures all of which uniformitytends to permit a better heat treatment in that the heat may pass evenlyaround and through all of theseveral sections.

With a laminated base formed in accordance with my invention I mightemploy a point made of a single casting or forging or one made of aplurality of sections similar to the base portion. In the drawings Ihave shown a point made of three sections l0, 11 and 12, securedtogether by rivets 13 as shown. The sections and 12 are provided withrecesses le for cooperation with dove tail projections 15 on each sideof the middle section 11. This arrangement has been provided so that all'tendency of the several sections to separate will be prevented byreason of the dove tailed arrangement, without having to depend on therivetsor the like for preventing separation of the It will therefore beobrivets in the points is to prevent relative longitudinal Idisplacementof the various sections going to form a single point and that tendencyfor lateral separation is prevented by reason of the novel dove tailedarrangement shown. lf it were desired to form a point of more than threesections `this could be accomplished by displacement of the severalsections providing as many cooperating lugs and.l recesses as the numbero sections (required.

It will be readily observed that by this method of making dipper teethand points I am not limited in size in any respect due to any presentrestriction by reason of casting alloy steel and subjecting the castingsto heat treatment. The only limit to size is that of use to which theteeth are to be applied. It ma be readily observed that the thichess ofthe teeth and points is not limited by a single casting as many or asfew sections may be fastened together as is needed to form a base eithernarrow or wide. In

`a similar manner the point may be made to conform to the tooth portionvthus reducing considerably the number of patterns necessary in thefoundry which immediately reduces the cost or' manufacture of theseparts.

While I have described more or less precisely the details ofconstruction of vmy invention, I do not wish to be understood aslimiting myself thereto, as I contemplate changes inl form andproportion of parts and the substitution of equivalents as circumstancesmay suggest or render expedient, without departing from the spirit of myinvention.

I claim:

1. A dipper tooth base Comprising a plurality of relatively thinsections of substan- -tially uniform thickness and similar shape,

with the flat sides of the sections secured together so that when saidbase is in position on a dippervbody the sections will be in edgewiserelation with respect to said body.

2. A dipper tooth base comprising a plurality of relatively thinsections of substantially uniform thickness and similar shape, with theflat sides of the sections secured t0- gether so that when said-base isin position on a dipper body the sections will be in edgewise relationwith respect to said body, said sections having interlitting members toprevent separation of the same.

3. A dipper tooth base comprising a plurality of relatively thinksections of substantially uniform thickness and similar shape, with theflat sides of the sections secured together s Q that when said base isin position on a dipper body the sections will be inYedgewis'erelationwith respect to said body, and means for preventingdisplacement of the several sections. p

4. A dipper tooth base comprising a piurality of relatively thin,sections of substantially uniform thickness andsimilar shape,

with the Het sides of the sections secured together so that when saidbase is in position on a dipper body the sections will be in edgewiserelation with respect to said body, certain of said sections havingopenings therethroughto receive means for attaching said base to adipper body.

5. A point for dipper teeth including a plurality of relatively thinsections of substantially uniform thickness secured totgether with theflat sides thereof in contact,

said sections being arranged to lie in edgewise position when said pointis secured in position-on a dipper body.

6r A. point for dipper teeth including a plurality of relatively thinsections of subs'tantially` uniform thickness secured together with theflat sides thereof in contact, said sections being arranged to lie inedgewise position when said point is secured in position on a dipperbody, and said sections having intertting members to prevent separationof the several sections.

7. A point for dipper teeth including a plurality of relatively thinsections of substantially uniform thickness secured together with thellat sides thereof in contact, said sections being arranged to lie inedgewise position when said point is secured in position on a dipperbody, and means for preventing displacement of the sections relativelyto one another.

8. A dipper tooth point made up of a plurality of relatively thinsections of ysubstantially uniform thickness secured together with theHat sides thereof in engagement, the sections having intercngageablemembers to prevent displacement thereof, and means for attaching saidpoint to a dipper body in such position that the sections will be inedgewise position with respect to said body.

l9. A dipper tooth adapted to be secured to a dipperbody and having apoint comprising a plurality of sections arranged side by side on edgeto the dipper body, dove tail connections between said sections, andtrans'- verse means passing through said dove tail connections forsecuring the sections together.,

Signed at Chicago Heights, Ill., this 2lst day of December, 1918.

WESLEY G. NICHOLS.

